Images the Saturn’s key rings, the F Ring, and also its shepherd moons obtained by NASA’s Cassini spacecraft. The narrow F Ring is located just external of the outer edge that the main rings. Two satellites sandwiching the F Ring slightly over and come the left that the center of the picture are the shepherd satellites Prometheus (inner orbit) and Pandora (outer orbit). Image credit: NASA / Kobe University.Ryuki Hyodo, a second-year phd student, and also Professor Keiji Ohtsuki the the Graduate institution of science at Kobe University have actually revealed the Saturn’s F Ring and also its shepherd satellites space a natural outcome that the final stage of development of Saturn’s satellite system. Your finding has actually just been released online in Nature Geoscience.

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Appearing prefer eyes ~ above a potato, craters sheathe the dimly lit surface of the moon Prometheus, among the shepherd moons because that Saturn’s F Ring, in this high-resolution image from Cassini’s beforehand 2010 flyby. This check out looks toward the trailing hemisphere the Prometheus which procedures 136 × 79 × 59 kilometer (85 x 49 x 37 miles). Photo credit: NASA / JPL / space Science Institute.Saturn, i m sorry is the 2nd largest world in our solar system, is recognized to have multiple rings and also satellites. In 1979, Pioneer 11 uncovered the F Ring, located 3,000 kilometre (1900 miles) beyond the outer edge the the A Ring. The F Ring is very active, v features changing on a timescale that hours.

The F Ring is also very narrow with a broad of just a couple of hundred kilometres, and has two shepherd satellites dubbed Prometheus and also Pandora, i m sorry orbit inside and outside the ring, respectively. Although the Voyager and also Cassini spacecraft later on made detailed observations of the F Ring and its shepherd satellites, their origin has not to be clarified.

According come the latest satellite development theory, Saturn provided to have ancient rings containing many more particles than they perform today, and satellites formed from spreading and also accretion of this particles. Throughout the final stage the satellite formation, multiple little satellites often tend to kind near the outer edge the the ring. ~ above the various other hand, observations by Cassini suggest that the tiny satellites orbiting near the external edge that the main ring system have a dense core.

While inner shepherd moon Prometheus contributes to the confinement of Saturn’s narrow F Ring, external shepherd moon Pandora dram a lesser role. NASA’s Cassini spacecraft acquired infrared, green and also ultraviolet pictures of Pandora in ~ a distance of roughly 52,000 kilometres (32,000 miles) ~ above 5 September 2005, i m sorry were merged to create this false-colour view. Pandora steps 104 × 81 × 64 kilometre (65 x 50 x 40 miles). Picture credit: PD-USGOV-NASA.In their simulations using in component computer solution at the National huge Observatory that Japan, Hyodo and Ohtsuki revealed that the F Ring and its shepherd satellites created as these tiny satellites v a dense core collided and also partially disintegrated. In other words, the system of the F Ring and its shepherd satellites is a herbal outcome the the formation process of Saturn’s ring-satellite system.

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This brand-new finding is expected to help elucidate the formation of satellite solution both within and also outside ours solar system. For example, the above formation system can additionally be used to the rings and also shepherd satellites the Uranus, i beg your pardon are comparable to those the Saturn.

In this computer system simulation, two satellites with dense cores collide at the current location the the F Ring. The collision go not damage the cores, which become two shepherd satellites, and also the dispersed particles dispersed in between the two satellites form the F Ring. Photo credit: Hyodo / Ohtsuki / Kobe University.Hyodo, currently visiting Institut de Physique du globe de Paris for his study from this spring (April 2015) remarked, “Through this study, we were may be to show that the current rings the Saturn reflect the formation and also evolution procedures of the planet’s satellite system.”

“As plans are underway in and also outside the Japan to explore the satellite device of Jupiter and the satellites of Mars,” claimed Ohtsuki, “we will proceed to unravel the origin of satellite systems, i beg your pardon is key to expertise the formation process of planetary systems.”